1. Field of the Invention
This invention concerns framing for a vehicle, and more particularly, to an improved rear frame structure for rear suspension components, primarily MacPherson type strut components which combine a shock absorber and a coil spring in a unitary assembly, the lower end portion of the strut component is operatively attached to a rear wheel support or spindle and the upper end of which is operably attached to the vehicle framing structure. The framing structure incorporates a pair of vertically oriented strut support towers spaced from one another laterally across the vehicle. A pair of laterally extending upper and lower cross beams extend between and are attached to the strut towers wherein a high degree of accuracy in tower spacing and alignment contributes to very accurate positioning thereof, particularly of the tower's upper end portions which are operably attached to the associated MacPherson suspension components. The subject arrangement provides an isolation structure between the suspension component's upper end portion and the framing structure for greatly reducing vibration and noise transmission during operation of the vehicle.
2. Description of Related Art
Prior to the present invention is was known to provide various reinforced rear framing structures and strut configurations have been designed to operatively mount the rear suspension components with the object of providing a comfortable ride and increased storage space within the vehicle body in the form of an enlarged luggage/cargo space.
For example, U.S. Pat. No. 4,408,794, for A Support Column for an Automotive Vehicle Wheel Suspension Assembly, issued Oct. 11, 1983, discloses a rear frame structure with support columns or suspension strut towers that are connected at an upper end by a thin-walled upper rear shelf panel and at a lower end by a substantially flat floor panel. With this construction, the suspension strut towers are designed to support rear wheel suspension components but are not readily adjustable relative to any supports for establishing a high degree of accuracy in spacing or parallelism.
In U.S. Pat. No. 5,350,214, for A Rear Body Structure for Automotive Vehicles, issued Sept. 27, 1994, opposing suspension strut towers are connected at their lower ends to special gusset constructions which are in turn connected to a floor cross member and are connected at their upper ends by gussets which are in turn connected to a panel-like rear shelve tray, thereby requiring additional means to stiffen the corners of a pass-through structure which reduces the opening size and the utility of the pass-through feature.
In U.S. Pat. No. 4,950,025, issued Aug. 21, 1990 for Automobile Rear Body Structures, a rear deck, fenders, inner panels and rear wheel houses are joined to form a compartment for receiving external forces such as from road shock imparted through the rear wheel suspension struts.
The framing arrangements disclosed in the previous prior patents provide various constructions and improvements to the vehicle body structures, they incorporate additional parts, assembly operations, and expense to achieve a sufficient degree of accuracy to provide a stable suspension strut platform for mounting suspension components. More particularly, the prior constructions do not provide the isolation of the suspension component from the strut tower and framing structure as in the subject embodiment. Resultantly, the suspension springs and shock absorbers cannot operate with high efficiency to dampen road caused vibrations while still isolating the vehicle body from feedback from the suspension components.
In addition to the previously discussed prior art, the following patents are disclosed to more completely disclose the state of the art. In U.S. Pat. No. 5,660,415, issued Aug. 26, 1997 for "A Torque Box Assembly for a Vehicle", a torque box for mounting a rear suspension trailing link is shown attached to a vehicle frame side rail and a body side rail for receiving external forces such as from road shock imparted through the rear wheel suspension.
In U.S. patent application Ser. No. 08/678,285, filed Jul. 11, 1996, entitled "Bracket With Floating Tap Plate for Connecting Vehicle Suspension to Body" a fastener for attaching a portion of a vehicle suspension to a vehicle body is disclosed.